• Title/Summary/Keyword: spatial weighting

Search Result 172, Processing Time 0.031 seconds

A Study on the Realization of Variable Spatial Filtering Detector with Multi-Value Weighting Function (계측용 공간필터의 가변적 다치화된 가중치 실현에 관한 연구)

  • Jeong, Jun-Ik;Han, Young-Bae;Go, Hyun-Min;Rho, Do-Hwan
    • Proceedings of the KIEE Conference
    • /
    • 1998.11b
    • /
    • pp.481-483
    • /
    • 1998
  • In general, spatial filtering method was proposed to simplify measurement system through parallel Processing hardware. Spatial filtering is a method of detection that we can get a spatial pattern information, as we process a special space pattern, to say, as we process spatial parallel process by using the spatial weighting function. The important processing characteristics will be depended in according to how ire design a spatial weighting function, a spatial sensitive distribution. The form of the weighting function which is realized from the generally used spatial filtering is fixed and the weighting value was already became a binary-value. In this paper, we propose a new method in order to construct adaptive measurement systems. This method is a weighting function design to make multi-valued and variable.

  • PDF

Integration of Current-mode VSFD with Multi-valued Weighting Function

  • Go, H.M.;Takayama, J.;Ohyama, S.;Kobayashi, A.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.921-926
    • /
    • 2003
  • This paper describes a new type of the spatial filter detector (SFD) with variable and multi-valued weighting function. This SFD called variable spatial filter detector with multi-valued weighting function (VSFDwMWF) uses current-mode circuits for noise resistance and high-resolution weighting values. Total weighting values consist of 7bit, 6-signal bit and 1-sign bit. We fabricate VSFDwMWF chip using Rohm 0.35${\mu}$m CMOS process. VSFDwMWF chip includes two-dimensional 10${\times}$13 photodiode array and current-mode weighting control circuit. Simulation shows the weighting values are varied and multi-valued by external switching operation. The layout of VSFDwMWF chip is shown.

  • PDF

Kalman-Filter Estimation and Prediction for a Spatial Time Series Model (공간시계열 모형의 칼만필터 추정과 예측)

  • Lee, Sung-Duck;Han, Eun-Hee;Kim, Duck-Ki
    • Communications for Statistical Applications and Methods
    • /
    • v.18 no.1
    • /
    • pp.79-87
    • /
    • 2011
  • A spatial time series model was used for analyzing the method of spatial time series (not the ARIMA model that is popular for analyzing spatial time series) by using chicken pox data which is a highly contagious disease and grid data due to ARIMA not reflecting the spatial processes. Time series model contains a weighting matrix, because that spatial time series model influences the time variation as well as the spatial location. The weighting matrix reflects that the more geographically contiguous region has the higher spatial dependence. It is hypothesized that the weighting matrix gives neighboring areas the same influence in the study of the spatial time series model. Therefore, we try to present the conclusion with a weighting matrix in a way that gives the same weight to existing neighboring areas in the study of the suitability of the STARMA model, spatial time series model and STBL model, in the comparative study of the predictive power for statistical inference, and the results. Furthermore, through the Kalman-Filter method we try to show the superiority of the Kalman-Filter method through a parameter assumption and the processes of prediction.

Evaluating Rebuilding Priority to Improve Residential Environment Using Spatial Weighting: A Case Study on Shinchun-Dong of Daegu Metropolitan City (공간 가중치를 이용한 주거환경 개선지역 우선순위평가: 대구광역시 신천동을 사례로)

  • Son, Seung-Hooi;Park, Ki-Heon;Um, Jung-Sup
    • Journal of the Korean Geographical Society
    • /
    • v.43 no.6
    • /
    • pp.961-980
    • /
    • 2008
  • It is usual to prioritize the blocks to rearrange residential environment by the responsible officer's intuition or a few specialist's experienced knowledge. The aim of this research was to evaluate rebuilding priority in the context of spatially weighted framework integrating resident's view. The spatial weighting for the variables related to evaluation of dwelling environment was derived from AHP (Analytic Hierarchy Process) approach through the analysis of resident's view. An empirical study for a case study site has been conducted to confirm the validity for the spatial weighting. The spatial weighting has frequently influenced in changing the rebuilding priority and was identified as the important predictor for the improvement sites of dwelling environment. The spatially weighted analysis made it possible to identify area-wide patterns of rebuilding priority area subject to many different type of thematic variables, which cannot be acquired by traditional field sampling. The spatially weighting derived by integrating various formats of spatial data into a comprehensive GIS database in particular, was ideally suited to displaying the objective distribution patterns for rebuilding priority. The result of this study would play a crucial role in dealing with public complaints for rebuilding priority since it could provide objective evidences in accordance with spatial weighting.

An In-depth Study on Applying Metric Weighting to Space Syntax (공간구문론에의 거리가중개념 적용에 관한 심층 연구)

  • Kim, Minseok;Piao, Gensong
    • Journal of the Architectural Institute of Korea Planning & Design
    • /
    • v.34 no.12
    • /
    • pp.49-54
    • /
    • 2018
  • Applying metric(distance) factor as weighting to spatial syntax is known to not contribute to the explanatory power for the human movement behavior as compared to the geometric(angle) factor according to the negative results of several related studies. However, Kim & Piao (2017) assumed that there is not a problem of the metric factor itself but a problem of the way of applying the metric factor as weighting, and presented a new possibility of the metric factor as weighting by proposing and verifying the methods of applying the metric weighting, which are different from the existing ones. The purpose of this study is to propose advanced methods of applying the metric weighting to space syntax, and to verify whether they contribute to the improvement of explanatory power of space syntax analysis. In this paper, we propose functions for combined depth of distance-step that combine the distance-weighted depth function with the step depth function and apply them to axial segment analysis to check the improvement of explanatory power of them.

AGRICULTURAL DROUGHT RISK ASSESSMENT USING REMOTE SENSING AND GEOGRAPHIC INFORMATION SYSTEM

  • Narongrit, Chada;Yeesoonsang, Seesai
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.991-993
    • /
    • 2003
  • The 4 sets of environmental variables dealing with meteorology, hydrology and physiography were analyzed to generate a spatial drought risk index of Phitsanulok province of Thailand. The analysis of K-mean and discriminant were applied to the set of the selective drought variables for grouping each of spatial variable set into 4 classes. The obtained 4 classes, based on group statistics, were thus recoded in the meaning of no risk, low risk, moderate risk, and high risk. The regression coefficient between recoded classes and a set of the selective environmental variables were then applied as spatial variable weighting on thematic dataset in GIS spatial analysis. The results showed that the weighting score of drought variable was highest in meteorological variable compared to other variables.

  • PDF

Estimating Optimal Potential Surface for Spatial Expansion of Built-up Area by Formulating WSM-AHP Method (WSM-AHP법의 정식화를 통한 주거지 확산 지역의 최적 잠재력 표면의 추정)

  • Kim, Dae-Sik
    • Journal of The Korean Society of Agricultural Engineers
    • /
    • v.50 no.3
    • /
    • pp.91-104
    • /
    • 2008
  • This study developed the WSM (weighted scenario method)-AHP method that can optimize the weighting value for multi-criteria to make GIS grid-based potential surface. The potential surface has been used to simulate urban expansion using distributed cellular automata model and to generate land-use planning as basic data. This study formulated the WSM-AHP method in mathematically and applied to test region, Suwon city, which located on south area from Seoul. WSM-AHP method generates potential map for each pair of weighting value for all criteria, which one criterion is weighted with high weighting value and the others use low weighting value, considering that the summation for all criteria weighting values should be "1". The potential change rate to the step of weighted scenario for weighting value of criteria is standardized like AHP intensity matrix in this study. From the standard potential change rate, WSM-AHP intensity matrix is completed, and then the optimal weighting value is calculated from the maximum eigenvector of the WSM-AHP matrix, according to the new WSM-AHP method developed in this study. The applied results of new method showed that the optimal weighting value from WSM-AHP is more resonable than the general AHP specialists' evaluation for weighting value. The another new finding of this study is to suggest the deterministic approach to optimize the weighting value for the distributed CA model, which is used to find new city area and to generate rational land-use planning.

Development of a potential evaluation method for urban expansion using GIS and RS technologies (GIS와 RS를 이용한 도시확산 포텐셜 평가기법의 개발)

  • Kim, Dae-Sik;Chung, Ha-Woo
    • Journal of Korean Society of Rural Planning
    • /
    • v.10 no.3 s.24
    • /
    • pp.41-51
    • /
    • 2004
  • This study aims to develop a potential evaluation method for urban spatial expansion using remote sensing (RS) and geographic information system (GIS). A multi-criteria evaluation method with several criteria and their weighting values was introduced to evaluate the score and quantification of the potential surface around the existing cities. The six criteria with one geographic factor, slope, and five accessibility factors, time distance from center of the city, national road, interchange of expressway, a big city, and station, were defined for the potential. RS techniques were applied for classification of the actual urban expansion maps between two periods, and GIS functions were used for score of accessibility criteria with a distance decay function from geographic, road and several point maps, which was developed in this study. The new methodology was applied to a test area, Suwon, between 1986 and 1996. In order to optimize the six weighting values, this study made new findings to search the optimal combination of the weighting values from new methodology, weighted scenario method for intensity order (WSM), combined with intensity order and AHP method, including a trial and error method for sensitivity analysis to make the intensity order. The optimal combination of the weighting values by the new method generated the optimal potential surface, considering spatial trend of urban expansion in the test area.

Estimation of Area Average Rainfall Amount and Its Error (면적평균강우량의 추정 및 추정오차)

  • Yu, Cheol-Sang;Jeong, Gwang-Sik
    • Journal of Korea Water Resources Association
    • /
    • v.34 no.4
    • /
    • pp.317-326
    • /
    • 2001
  • This study evaluates the errors involved in the area average rainfall amounts estimated by the arithmetic mean method, the Thiessen's weighting method, and the optimal weighting method from the estimation theory. This study was applied to the upstream part of Nam-Han river basin (upper part of Youngwal) and the following results could be obtained. First, in case the raingauges are located evenly over the basin, no obvious difference can be found in the area average rainfall amounts from the arithmetic mean method or from the Thiessen's weighting method. However, as these two methods cannot consider the spatial variability of rainfall, the estimation error could be higher when the spatial variability of rainfall is high. In our application the estimation error from the arithmetic mean method or the Thiessen's weighting method was also found to be higher than that from the method from the information theory, which considers the spatial variability of rainfall. Thus, we could conclude that for the rainy season of Korea or for the mountain area when and where the spatial variability of rainfall is high, a proper method of considering the spatial variability of rainfall should be used regardless of the basin size. The isohyetal method generally used for the large basins or the optimal weighting method from the estimation theory used in this study could be good alternatives for this case.

  • PDF

Speckle noise reduction in SAR images using an adaptive wavelet Shrinkage method

  • Kim, Kwang-Yong;Jeong, Soo;Kim, Kyung-Ok
    • Proceedings of the KSRS Conference
    • /
    • 2002.10a
    • /
    • pp.303-307
    • /
    • 2002
  • Although Synthetic Aperture Radar(SAR) is a very powerful and attractive tool, automatic interpretation of SAR images is extremely difficult because of several reason. Spatially, speckle noise reduction in SAR images is important step to interpret the SAR image at the preprocessing step. The speckle noise in SAR images is modeled to be multiplicative, and therefore, a signal-dependent noise. So, it has deflated many image-denoising algorithms that are based on additive noise model. In this paper, we propose an adaptive wavelet shrinkage method for speckle noise reduction in SAR images by analyzing the high frequency level in detail. We first decompose minutely the high frequency level to analyze the noise level. And then, we determine the weighting threshold value per the level, and layer. Finally, using those weighting threshold, we produce the efficient wavelet shrinkage method. So, this method not only reduces the speckle noise, but also preserves image detail and sharpness.

  • PDF